The Evolution of the Insanity Defence in England and Wales

The Evolution of the Insanity Defence in England and Wales

The insanity defence in English law is typically pleaded in the crown court, where the statutory special verdict applies. This dates back to the Criminal Lunatics Act 1800. Prior to this, only the common law insanity defence applied, which resulted in a plain acquittal (although often civil detention occurred given the profound degree of impairment required to persuade a lay jury of insanity before medical experts were permitted in court, the first case being in 1760). This still applies when the insanity defence is successful in the magistrates court. It results in a verdict of not guilty by reason of insanity, although between 1883 and 1964 the verdict was 'guilty of the act but insane at the time' (introduced by the Trial of Lunatics Act 1883, with the original wording restored by the Criminal Procedure (Insanity) Act 1964). This outcome was unacceptable to monarch and parliament for the man who attempted to assassinate King George III, Hadfield, and so emergency legislation was passed to enable his detention.

Hadfield was a veteran of the First War of the Coalition, and had been part of the bodyguard of the Duke of York at the battle of Lincelles, where he received a serious head wound from a sabre. It was clear that prior to the injury he had been a loyal and brave subject. It was likely that the visible head injury (counsel invited the jury “to inspect the membranes of the brain itself”) and his previous loyal service helped persuade the jury that this behaviour was contrary to his pre-morbid character. This was the first case where the concept of partial insanity was accepted as the basis of an acquittal. Hadfield’s counsel, Erskine, argued that delusion “unaccompanied by frenzy or raving madness [was] the true character of insanity”. Hadfield’s delusion was that he must die to save the world, but he could not die by his own hand. Thus he contrived to be killed in the course of an assassination attempt. 

The statutory special verdict allowed for only one disposal until recently - detention at Her Majesty's Pleasure. Once the death penalty was abolished and the defence of diminished responsibility was introduced for homicide, the insanity defence became less and less attractive given the prospect of indefinite detention. The insanity defence became virtually obsolete. However the Criminal Procedure (Insanity and Fitness to Plead) Act 1991 gave judges the choice of four disposal options, later reduced to these three:

1) A hospital order with or without a restriction order (mandatory for homicide where there is a mental condition)

2) Supervision order

3) Absolute discharge

Mackay found that this legislation resulted in increasing numbers of successful insanity defences. 

So rather than being motivated by compassion, the statutory special verdict was a regressive step. During the 19th century it was widely considered that the insane were still capable of being deterred, and so the detention of the insane had a punitive element to it. Indefinite detention very often did amount to detention for life, and the conditions in the asylums of the time were appalling by modern standards. Prime Minister Gladstone considered the special verdict 

"an inducement...to morbid minds for the commission of crime by an apparent declaration of innocence in the teeth of the facts."

This perception led to the substitution of the original verdict of 'not guilty by reason of insanity' with 'guilty of the act but insane at the time', as noted above.